Ring-opening polymerization organometallic polymers

Thus, the second approach to the synthesis of poly(organophosphazenes) involves the introduction of the organic (or organometallic) side groups at the cyclic trimer level, followed by ring-opening polymerization of the substituted cyclic trimer to the high polymer (reaction (ll)).23... 

Organometallic polymers formed by ring-opening polymerization of ferro-cenophane 01MI141. 

The main method of synthesis for polyphosphazenes [4-6] involves the thermal ring opening polymerization of monomer 5 to uncrosslinked high polymer 6, followed by solution state nucleophilic replacement of the chlorine atoms in 6 by organic or organometallic side groups. The overall process is illustrated in Scheme I. 

Ring-opening polymerization (ROP) has seen broad utility for synthesizing main-chain organometallic polymers. Initially reported by Rauchfuss [9], and thoroughly developed by Manners and coworkers [10], the transformation from 10 to 11 (Schane 1.4) has been optimized to include various conditions for polymerization such as thermal, anionic, photo, and metal-mediated polymerizations Both solution and solid-state polymerization have also been reported. Molecular weights on the order of 10 Da have been achieved and the ability to prepare monomers of varying functionahty has assisted... 

Some examples of sequence-controlled polymers prepared by ring opening polymerization of cyclic esters have been reported. For instance, Thomas, Coates, and coworkers reported a very original method for the synthesis of alternating aliphatic polyesters.These authors used a stereoselective yttrium-based organometallic catalyst to control comonomer sequences. It had been previously shown that the polymerization of a racemic mixture of p-butyrolactone in the presence of this catalyst led to the formation of... 

Method of synthesis ring-opening polymerization of p-dioxanone in the presence of organometallic catalyst (e.g., zirconium acetylacetone) Li, Y Whng, X-L, Yang, K-K Wang, Y-Z, Polym. Bull., 57,873-880, 2006. 

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